1. Field of the Invention
This invention relates to a clamp device of a height gauge, and more particularly to improvements in a device for clamping to a support a feed box connected to a slider through a fine movement means, for effecting a fine movement of the slider.
2. Description of the Prior Art
The most common clamp device of the conventional height gauge has been constructed such that the feed box is screwed onto a support, whereby it has been impossible to suitably clamp the feed box as a slider is moved, thereby resulting in very low controllability. Therefore, there has been adopted that a clamp device of a height gauge, wherein the feed box can be clamped or released from the clamping while the slider is moved through operation of a lever.
However, with the lever-operation type clamp device of the prior art, the feed box abuts against the support ununiformly when the clamping is released, whereby it has been difficult to smoothly move the feed box and the slider along the support. More specifically, FIG. 1 shows the conventional clamp device, in which a slider 2 and a feed box 3 are slidably supported by a support 1, respectively, and the slider 2 and the feed box 3 are connected to each other through a fine movement means 4.
A substantially L-shaped lever 5 is rotatably supported by the feed box 3 through a pivot 5A, and one end of this lever 5 can abut against the support 1 through a sheet spring 6 secured to the feed box 3. The other end portion of the lever 5 extends along the slider 2 and formed with a handgrip 7. A block member 8 is affixed to the sheet spring 6, a compression coil spring 9 is confined between this block member 8 and the lever 5, and the aforesaid one end of the lever 5 is biased by this compression coil spring 9 to abut against the support 1 through the sheet spring 6. In consequence, with the conventional clamp device of the height gauge, when the handgrip 7 is grasped to release the clamping, a moment to tilt the feed box 3 is exercised by the compression coil spring 9, whereby the feed box 3 and the support 1 are brought into an ununiformly abutted state, thus making the feed box 3 and the slider 2 slide not smoothly. Furthermore, the compression coil spring 9 is confined between the lever 5 and the sheet spring 6 of the feed box 3, so that no satisfactory clamping force can be obtained, thereby decreasing the durability of the clamping force.